LETTING & ESTATE AGENT

The damp dilemma: What causes condensation and how to stop it

The damp dilemma: What causes condensation and how to stop it

One of the biggest problems landlords face during the colder months is condensation and mould in their buy-to-let properties.

Landlords often find themselves condemned for letting properties that suffer with condensation and mould problems, but often it is a tenant's lifestyle that causes the issue. The key for you as a landlord is to establish what is causing the problem and deal with it quickly and effectively.

That means being able to answer some key questions...


WHAT CAUSES CONDENSATION?

Condensation is formed when warm air, which is full of moisture, meets a cold surface.

An example would be steam-laden air from cooking rising to a cold ceiling or window pane and turning into water droplets.

However, while the droplets on a window are easily visible, condensation that forms on walls and ceilings is not so easy to stop. The moisture can therefore be absorbed into the plaster, resulting in that dreadful mouldy smell and black mould spores forming on the surface.

In serious cases, black mould can become toxic and do serious harm to health.

 

WHY IS CONDENSATION WORSE IN WINTER?

In the colder months, surfaces naturally become cooler. However, we all still shower and cook food so all that moist air hits those surfaces and forms condensation.

The difference in summer is those surfaces are naturally warmer, plus most properties are well ventilated in summer simply because it's too hot to keep the windows closed... which leads on nicely on to the issue of poor ventilation.

 

SO, BAD VENTILATION IS THE BIGGEST CAUSE OF CONDENSATION, RIGHT?

A better way to look at it is this: Good ventilation can be the best way to halt condensation in its tracks.

A feeding ground for condensation is a poorly ventilated room. Kitchens and bathrooms are most prone to the dreaded droplets due to moisture created by cooking, showers and baths. But bedrooms can also be a happy hunting ground for moisture and we'll come on to that next.

If those rooms are not well ventilated, condensation has free rein to turn into nasty, smelly black mould. And this can do as much damage to your tenant's health as it can to your buy-to-let property.

 

WHY DO MY TENANTS COMPLAIN ABOUT CONDENSATION ON THEIR BEDROOM WINDOWS?

As we said above, bedrooms can be prone to serious cases of condensation and mould. 'But the tenants aren't cooking or showering in their bedrooms', we hear you cry.

You're right, of course. But they are probably sleeping in their rooms for upwards of seven hours a night. Nights are generally colder than days and if the property's heating is off, the moisture from a sleeping tenant's breath will form condensation on window panes.

That can lead to nasty black mould spores along rubber seals and sealant beads, which are extremely tough to remove.


SHOULD MY TENANTS KEEP THE HEATING ON THEN?

Absolutely. The second biggest cause of internal condensation is a cold property.

This could be down to your tenants trying to save money on heating bills or it could be due to the property boasting an inadequate heating system. Either way, a cold property working in conjunction with plenty of moist air from cooking, showering and sleeping is a prime breeding ground for condensation and mould.

 

IS CONDENSATION THE SAME AS DAMP?

Most of the time, condensation is caused by the poor habits of those living in a property. Damp is generally caused by the property itself, although one certainly helps the other.

Building defects, which are very much an issue for you as a landlord, generally cause damp. The good thing is damp is easy to spot and remedy.

A leaky roof, poor damp proof course or burst pipes will create localised damp, allowing you to pinpoint the problem quickly and rectify it.

Condensation in a bedroom, for example, could be caused by moisture from the kitchen or bathroom travelling through the property, meaning an 'all in' approach is required to eliminate it.

 

HOW DO YOU GET RID OF CONDENSATION?

As we alluded to earlier, rental property condensation is more often than not caused by the way your tenants are living. Which means education is the way forward.

That said, if your property is lacking in good ventilation and insulation, this will need to remedied first.

As a landlord, the 2018 changes to Energy Performance Certificate regulations in residential lettings should have seen you check, and improve if needed, your buy-to-let property's energy efficiency.

Good quality wall and roof insulation, plus modern, double glazed windows can all help keep the heat in a property, greatly reducing condensation. Plus, your tenants are more likely to keep the heating on during the colder months if they know very little of that heat is escaping through walls and the roof.

Make sure your property's kitchen and bathrooms have extractor fans fitted - this will help that moist air ventilate into the outdoors rather than clinging to walls and window panes.

 

WHAT ADVICE SHOULD I GIVE MY TENANTS?

Encourage them to keep the property warm at all times during the winter. No room should fall below 18 degrees Celsius at any time and the heating should run in the background all day.

Fluctuating temperatures are like a red rag to a bull when it comes to condensation, so keeping rooms and therefore walls, windows, ceilings and other surfaces condensation will form on consistently warm will help keep it at bay.

If your tenants are battling an existing condensation problem at your rental property, purchase them a dehumidifier and encourage them to use it in conjunction with keeping the property warm.

Other advice you can give your tenants to get rid of condensation includes:

  * Open a window or use a cooker extractor when cooking and keep lids on saucepans

  * Keep the kitchen door closed while cooking so all moist air vents through the window or fan

  * Keep the bathroom door shut when bathing or showering and open a window to allow the steam to vent

  * Even in the winter, open a few windows around the house for a short time to allow some fresh air to circulate throughout the property

  * Never block air vents or air bricks

  * Avoid drying clothes on radiators


WHAT CAN I DO AS A LANDLORD TO STOP CONDENSATION?

  * As well as providing guidance to your tenants on ventilation and adequate heating, you should do the following as a landlord:

  * Ensure the property is free from damp. Check for leaking roofs, guttering, downpipes and blocked drains. Also call in an expert to check your property's damp proof course

  * Your rental property should already meet modern insulation requirements due to the energy performance regulations that came in earlier this year. But is there anything more you can do?

  * Keep your property's heating system maintained by gas safe experts. Not only could this save you money in the long run, it will also keep your tenants happy


If you do have a black mould problem in your rental property, use an expert to deal with the issue. Black mould can be toxic.